A common method of taking a panoramic image with a digital still camera is for the user to use the digital still camera to take multiple overlapping images, transfer them to a computer, process them on the computer and to stitch them together using a stitcher such as, for example, Apple's “QuickTime VR”.
In the capturing stage, the user typically needs to fix the exposure, white balancing, and focus, to ensure colour consistency. This can be simplified by having a “panoramic mode”, which is commonly available in many digital still cameras. The user decides on the orientation of the camera, whether landscape or portrait, and also whether to pan the camera left or right. The relevant instructions are input to the camera. Next, the user operates the camera to take multiple overlapping snapshots with appropriate overlap. The responsibility of ensuring there is sufficient overlap lies with the user. The process requires the user to pause between each shot to perform framing. Some cameras provide visual assistance for framing the next panoramic image by displaying part of the previous snapshot. Although it removes most of guesswork, the user will still need to stop and perform manual framing for each shot, which is relatively disruptive compared to taking a single snapshot.
Next, in the stitching stage, the user typically transfers all the images to a computer, and manually selects panoramic sequences from a mixture of panoramic and still snapshots. The panoramic image sequences are brought into a stitching application for stitching one at a time. The user may also need to provide the orientation and pan direction information to the stitcher. The result of the stitching process is a panoramic image. Although most stitchers are fully automatic, the process of sorting and searching snapshots for panoramic image sequence for stitching adds unnecessary work. This is illustrated in FIGS. 3 and 4.
There has been proposed to use the “movie” mode of more advanced digital cameras to capture many images and to use those images to form a panoramic image. By using “movie” mode, a large number of images are taken (normally 30 per second) so there should always be adequate overlap. Most users take several seconds to pan a large panorama, so such cameras can capture over 200 images for one panoramic image. This requires very powerful, and fast, processing and significant memory. As such only very powerful digital cameras can be used, and such cameras are very expensive. In addition, the image resolution in movie mode is typically much smaller than in still image mode.